Normally you ask your assistant to set the light on, start the ventilator, pump etc etc.
This is the other way round.
By pressing a key the ESP32 (using a special library) sends data to your Google Home Assistant.
So press the button and your assistant will tell you the temperature in your mancave.
Or attach a sensor and let the Assitant tell you that there is an intruder.
Or give a warning on your assistant when a water level reaches a certain point. etc. etc.
Full schematics and code on my weblog.
Easily adaptable for many purposes.
http://lucstechblog.blogspot.com/2020/0 ... art-2.html
Luc